The main aim of this study was to investigate the causes and management of conflict in secondary schools at Bahir Dar city administration zone. In doing so, attempts were made to identify the causes of conflict between teachers to principals, between teachers to teachers, between teachers to students, between students to students and between students to principals and strategies applied by principals to manage school conflict. Hence, the sample population used in the study consisted of 146 by simple randomly selected teachers, 3 principals and 60 students selected by purposive non-randomly sampling drawn from the three schools of Bahir Dar City Administrative Zone. Questionnaire, interview and focus group discussion were used data collecting tools. The percentages, mean, aggregate mean and the standard deviation were the statistical methods used in analyzing data. The study showed that communication problems, lack of professional commitment, different perceptions, leadership styles of the principals, disagreement over the strict application of rules and regulations and students disrespect to others were some of the common sources of conflicts which frequently occurred in secondary schools. In addition, compromising, accommodating and collaborating were found to be the most frequently used techniques of managing school conflict. In general, the findings revealed that secondary school heads always encounter conflicts in different aspects of their daily operations, Therefore, for the effectiveness of managing conflict processes and for getting balanced view of conflicts, special training for principals, students and teachers were recommended.